Answer in brief
CVE-2026-125338 records a Medium severity (CVSS 4.5) vulnerability in Winter CMS: Stored XSS through cached Brand Settings and Editor Settings custom styles. The current sources do not mark it as known exploited. The current feed maps winter/wn-backend-module (composer), wintercms/winter (generic), winter/wn-backend-module (packagist). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 4.5. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps winter/wn-backend-module (composer), wintercms/winter (generic), winter/wn-backend-module (packagist). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| winter/wn-backend-modulecomposer | <=1.2.13 | 1.2.14 |
| wintercms/wintergeneric | <1.2.14 | 1.2.14 |
| winter/wn-backend-modulepackagist | >=0 <1.2.14 | 1.2.14 |
Published upstream
Nov 10, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Nov 10, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Aug 20, 2026
Winter CMS is a content management system built on the Laravel PHP framework. Prior to 1.2.14, BrandSetting::renderCss() and EditorSetting::renderCss() store raw LESS compiler output with Cache::forever() but apply strip_tags() only to the value returned on a cache miss. The first render after saving custom CSS appears sanitized while priming an unsafe cache entry, and later cache hits return unsanitized output into the backend style element, allowing a user with backend.manage_branding or backend.manage_editor to cause stored cross-site scripting when another backend page renders the styles. The styles also appear on unauthenticated backend sign-in, password restore, and password reset layouts. This issue is fixed in version 1.2.14.
Quoted source text, attributed separately from HOL analysis.